On the 23rd day of June, 1923, the Howard-Sevier Road Improvement District No. 1 of Howard and Sevier counties, Arkansas (hereafter called district), instituted an action in the chancery court of Howard” County against delinquent lands. This case was numbered 211 on the docket of the trial court. The complaint alleged the organization of the district and the levying of assessments under the authority of the act creating the same and the failure to pay these assessments. The complaint set forth a list of the supposed *65owners and a description of the lands returned delinquent, together with the amount of the assessment and penalty set opposite the names. It was alleged that the assessments, penalties, interest and cost had not been paid on the lands mentioned. The prayer was that notice be given of the pendency of the action as provided by law, and that, unless the sums due were paid, a judgment be entered for the several amounts and for the sale of the lands described, to satisfy the same. After the institution of the suit, John C. Gardner, the receiver of the district, was joined as party plaintiff. .
J. M. Hunt and others, taxpayers in the district, filed an answer denying the allegations of the complaint, and set up affirmatively that the commissioners of the district had wholly failed to comply with the law requiring them to obtain and file a certified copy of the list of lands alleged to be delinquent. The parties filing the answer as defendants in the above cause also instituted an action in the Howard Chancery Court against the district and its commissioners, for themselves and “all those who have a general common interest with them in this suit.” This case was numbered 258 on the docket of the trial court. In their complaint they attacked the validity of the assessment of benefits as a whole, which the district and the receiver were attempting to collect, in their suit against the lands of the district. They set up in detail the causes which they alleged made the assessment as a whole invalid. They alleged in substance that the assessment of benefits sought to be charged against their lands was an arbitrary legislative assessment, the Legislature having -ratified and adopted an invalid assessment made by the board of assessors under a void act; that the assessment was so excessive as to amount to a confiscation of property; that it was in excess of any possible benefit to the property by reason of the improvement, and was greater in amount than the value of all the property in the district; that the attempted assessment was by the zone system, in which none of the elements affecting the benefits to *66their property were considered; that they had never had a day in court to challenge the assessment of benefits. They alleged that they were not seeking to avoid or repudiate any just and legal assessment that might be made against their property by reason of the construction of the improvement; that they were ready and willing to submit to any just and proper assessment of benefits made in the manner provided by law. They prayed that the assessment of benefits now standing against their lands be canceled, and that the district be restrained from prosecuting the suit for the collection thereof, and that a reassessment of benefits by reason of the improvement be ordered, to the end that a fair, proper and legal assessment of benefits be ascertained and fixed.
The answer of the district and its receiver alleged the appointment of a receiver under the terms of the act creating the district, and set up and made an exhibit to the answer a copy of the decree of the United States District Court of the Western District of Arkansas, validating $380,000 of the bonds of the district “secured by first mortgage on the assessment of benefits.” All of the allegations of the complaint were denied except as to the due organization of the district and the qualification of the assessors and the making of the assessment by them. The'answer admitted that the assessment made by the assessors was under a special act passed at a special session of the Legislature, which session was declared void by the Supreme Court. They alleged that such assessment was afterwards validated by act Noi 13 of the special session of the General Assembly in January, 1920; that, after the assessment was thus validated, a large amount of bonds were issued and sold and the proceeds used in the construction of the roads provided for under the original act creating the district and act No. 13, supra, amending the same. It was further alleged in the answer that on the 9th of April, 1921, T. G. Kennedy and others, for themselves and all other taxpayers in the district, instituted an action in the *67Howard Chancery Court against the commissioners as representatives of the district, and also in their individual capacity, in which suit they attacked the validity of the assessment of benefits as a whole, alleging that the same was arbitrary, discriminatory, and confiscatory, in violation of the due process clause of the Constitution of the United States, and also contrary to the Constitution of the State of Arkansas. It was alleged that the district duly appeared and was made a party to the suit, and answered, denying all the grounds upon which the validity of the assessment of benefits was challenged. It was also alleged that the Howard Chancery Court rendered a decree in that cause sustaining the validity of the assessment of benefits, and that no appeal had been prosecuted from that decree; that the issues in the suit of Kennedy et at. against the district and its commissioners were identical .with the issues in the present suit; that such suit was a class suit instituted by the taxpayers in the district in their own behalf and also for all other taxpayers within the district, and the district and receiver pleaded that the decree in that case sustaining the assessment of benefits was res judicata of the present action.
The causes were consolidated and tried together in the chancery court. Testimony was adduced on the issue as to the validity of the assessment of benefits, and the cause was heard upon this testimony and upon the pleadings and exhibits in the consolidated causes. Among other things the court found that “there is no merit to the plea of res judicata made by the plaintiffs in cause No. 211 and by the defendants in cause No. 258; that none of the parties plaintiff in case No. 258 and defendants in case No. 211 were parties to the cases pleaded in bar.” The court further found that “the attempted assessment of benefits is arbitrary, confiscatory, and an unwarranted exercise of the taxing powers.” The court thereupon entered a decree canceling the assessment of benefits and enjoining the collection thereof or any levy made for that purpose, and directed that the commis*68sioners appoint assessors to “assess the real, jnst, fair, true and actual benefits as have accrued against the several tracts 'and parcels of land in the district by reason of the construction of said improvements.” The plaintiffs in case No. 211 and defendants in case No. 258 excepted to the findings and decree of the court, and duly prosecuted this appeal.
1. • It will be observed from the above resumé of the pleadings in these causes that the appellees contend that the assessment of benefits which the appellants are attempting to enforce is, as a whole, an invalid assessment, for the reasons alleged. On the other hand, the appellants contend that the assessment of benefits was valid, and that such issue had already been determined by the former decrees of the Howard Chancery Court and the District Court of the United States, Western District of'Arkansas, adversely to the appellees, which decree they pleaded as res judicata of the matters raised by the appellees in their pleadings in these causes. Therefore the first question for our determination is whether or not the court erred in holding that there was no merit in appellants’ plea of res judicata.
The appellants’ pleadings and the exhibits thereto established the following facts, which are undisputed by the appellees, to-wit: On the 9th of April, 1921, T. Gr. Kennedy and others instituted an action in their own right and for all other taxpayers within the district' against the district and the commissioners in their representative and individual capacities, in which the assessment of benefits now under review, as a whole, was challenged on the ground that it was “unfair, unjust, discriminatory, confiscatory■ and not uniform,” and in violation of the due process -clause of the Constitution of the United States and contrary to the Constitution of the State of Arkansas, and therefore void; the cause was heard upon the pleadings raising the issue of the validity of the assessment, and the evidence adduced, and a decree was entered on the 9th of November, 1921, sustaining the validity of the assessment of *69benefits, and dismissing so much of the complaint in that, action as challenged the validity of such assessment for want of equity.
The appellees contend that they were not parties to that action, and hence were not bound by the decree, citing the ease of Cooper v. McCoy, 116 Ark. 501, and other cases which hold that, in order that a former judgment may constitute a bar to another suit, it must be rendered in a proceeding between the same parties, or their privies, involving the same subject-matter and cause of action, and must be determined on its merits. The same subject-matter was involved in the case of Kennedy et al. v. District as is involved in these consolidated causes, and that cause was heard upon its merits, and the cause of action was the same, as to the validity of the assessment of benefits.
The only remaining question is whether the appellees here, although not parties by name in the suit of Kennedy et al. against the district, were, in law, parties because of the fact that Kennedy et al. had instituted the action in their own right and for the benefit of all other taxpayers in the district. So far as we are aware, this precise question has never before been decided by this court, and is therefore one of the first impression in this State.
Our statute (§ 109i8, C. & M. Digest) provides:
“"Where the question is one of a common or general interest of many persons, or where the parties are numerous, and it is impracticable to bring them all before the court within a reasonable time, one or more may sue or defend for the benefit of all.” This statute is decisive of the question, and it but declares the doctrine which is supported with practical unanimity where considered in other jurisdictions.
Numerous authorities are cited in the briefs of appellants to sustain this view. Out of the array we select the case of Harmon v. Auditor of Public Accounts, 123 Ill. 122, which is fairly representative of the others. In that case an action was instituted by certain prop*70erty owners against the town of Mount Morris, Illinois, and its officers and the Chicago & Iowa Eailroad Company, to enjoin the town and its officers from issuing bonds to the railroad company. The issue was joined as to the right of the defendant town to issue the bonds, and the cause was finally adjudicated, denying the plaintiffs the relief sought. After this adjudication, four other taxpayers and property owners of the town instituted an action against certain bondholders and officers of the town, county and State, seeking to personally enjoin the collection of taxes upon their property for the payment of bonds issued to the railroad company. Judge Magruder, speaking for the Supreme Court of Illinois, of the action first brought by the taxpayers, among other things said: “The Pinckney bill was filed by certain property owners and taxpayers, as representatives of a. class. Though not formally stating that it is filed on behalf of all the other taxpayers in the town, yet it constantly refers to them and their interests in the questions involved.” And then, speaking of the last action brought by other taxpayers, he said: “The present suit was begun by Harmon and others, also taxpayers and property owners of the town, as representatives of the same class for whose benefit the Pinckney bill was filed. The complainants in this proceeding were represented by the complainants in the former suit, and are therefore bound by the decree therein entered. The remedy in suits of the character here indicated is in the interest of a class of individuals having common rights that need-protection, and, in the pursuit of that remedy, individuals have the right to represent the class to which they belong. This jurisdiction, in some respects, rests on the principles of a proceeding in rem. We therefore think that there is sufficient identity between the parties filing the present bill and those who filed the bill in the Pinckney case to justify the pleading ■ of the decree entered there as res judicata in this case.” And, further along, he announces principles which are apposite to the case at bar as follows: “The value of a plea of *71former recovery is not to be determined by the reasons which the court rendering the former decree or judgment may have given for doing so.. Nor is such former judgment or decree conclusive only as to questions actually and formally litigated. It is conclusive as to all questions within the issue, whether formally litigated or not. The principle of res judicata reaches further. It extends not only to the questions of fact and of law which were decided in the former suit, but also to the grounds of recovery or defense which might have been, ■ but were not, presented.”
In addition to the authorities cited in appellants’ briefs, see Freeman on Judgments, § 178; Elreno v. Cleveland Trinidad Paving Co., 107 Pa. 163; Gallagher v. Moundsville, 34 W. Va. 730, 12 S. E. 859; Ashton v. Rochester, 133 N. Y. 187, 30 N. E. 965, 31 N. E. 334; Dewey v. St. Albans Trust Co., 60 Vt. 1, 12 Atl. 224; Cincinnati v. Emerson, 57 Ohio St. 132, 48 N. E. 667.
2. The judgment of the District Court of the United States, Western District of Arkansas, in which the Guardian Savings & Trust Company, as trustee for bondholders, instituted an action against the district and its commissioners, and in which the plaintiff sought t-o validate and collect the first installment on mortgage bonds of the district in the sum of $380,000, was likewise res judicata of the appellees’ contentions in the ease in hand. The district, in that case, represented the taxpayers, and they were bound by the judgment- of the Federal court. Orcutt v. McGinley, 148 N. W. 586, 96 Neb. 619; Stone v. Wynn, 176 S. W. 933, 165 Ky. 9; Rose v. Port of Portland, 162 Pac. 498, 82 Ore. 541; Town of Tallassee v. State, 89 So. 514, 206 Ala. 169; Pear v. East St. Louis, 113 N. E. 60, 273 Ill. 501; 1 Freeman on Judgments, 4th ed. § 178; 2 Black on Judgments, 1st ed. 584, and numerous other authorities cited in appellants’ briefs.
The issue in the Federal court case as to the validity of the, bonds necessarily involved the issue as to whether there had been a valid assessment of benefits, for, if there *72was no valid assessment of benefits, there could be no valid issue of bonds. Western Randolph County Rd. Imp. Dist. v. Clifford, 150 Ark. 94. It is not pretended that the action in the Federal court was collusive or simulated between the bondholders and the district to have the first issue of -bonds of the district validated. As the district represented the taxpayers, it was bound to plead for them any defense that could have been set up which would have rendered the bonds invalid, and a good defense would have been that, for any reason whatsoever, there was no valid assessment of benefits. The district could, and should, have pleaded such ■ defense for the benefit of the taxpayers. See Ellis v. Clark, 19 Ark. 420; Morris v. Curry, 41 Ark. 75; Jones v. Terry, 41 Ark. 230; Church v. Gallic, 76 Ark. 423; Ederheimer v. Carson Dry Goods Co., 105 Ark. 488; Jimmerson v. Fordyce Lbr. Co., 119 Ark. 413.
The judgment of the United States District Court, after setting out the bonds, recited: They are “the valid obligations of said district, and are each duly secured by a first mortgage on the assessment of benefits of said district, bearing even date -to the bond issue, and duly recorded.” The judgment in that case was duly pleaded and in evidence in these consolidated causes. It was the duty of the trial court to give full faith and credit to 'this judgment. State ex rel. Craighead County v. St. Louis-S. F. R. Co., 162 Ark. 443; Shaw v. Polk, 152 Ark. 18; Davies v. Patterson, 137 Ark. 187; Harris v. Harris, 142 Ark. 267.
The facts of this record present a typical case for the application of the doctrine of res judicata above set forth, and exemplify the wisdom of the rule declared by our statute. This was a large district of several hundred taxpayers. If, at the end of two lawsuits involving -the validity of an assessment of benefits in this district, in which all the taxpayers thereof were duly represented and in which it was adjudged that the assessment of benefits was valid, other taxpayers could bring new suits, and so on down, until every taxpayer by name *73had been excluded, then indeed the only, security upon which the bonds were issued and sold and the money furnished to make 'such improvements would be as flickering and insubstantial as the “borealis race.”
The rationale of the doctrine of res judicata is well expressed by Judge Mitchell, in State of Wisconsin v. Torinus, 28 Minn, 175-179. “The doctrine of res judicata,” says he, “is founded upon two maxims of the law, one of which is that ‘a man should not be twice vexed for the same cause,’ the other that ‘it is for the public good that there be an end of litigation;’ and it is undoubtedly true that, if there be any one principle of law settled, it is that, whenever a cause of action, in the language of the law, ‘transit in rem adjudicatam/ and the judgment thereupon remains in full force and unreversed, the original cause of action is merged and gone forever. After judgment on the merits, a party cannot afterwards litigate the same question in another action, although some argument might have been urged on the first trial that would have led to a different result. Such a judgment is final and conclusive, not only as to matters actually decided, but as to every other matter which the parties might have litigated and had decided as incident to and essentially connected with the subject-matter of the litigation, as the facts then existed. The discovery of new evidence, not in the power of the party at the former trial, forms no exception to the rule. The doctrine is so just, and so necessary to the peace and good order of society, that we have no desire to either modify it or unreasonably limit its application.”
The district, as we have seen, represented all the taxpayers in the Federal suit.
Since Kennedy and the others who instituted the original action attacking the validity of the assessment of benefits as a whole, which appellants are here seeking to enforce, represented the appellees and a-11 the taxpayers and property owners of the district who were in the same class, it follows, from our statute and the above authorities, that the appellees were parties to that *74original action the same as if they had been made so by name. The appellees are bound by the unreverséd judgment of the trial court in that case, determined on the merits, that the assessment of benefits was valid. There is no contention here that that cause was a simulated or collusive lawsuit' on- the part of Kennedy and the others named with him and the district and its commissioners to obtain a judgment of the court validating the assessment. That it was. not a collusive suit is abundantly shown by the opinion of this' court in the case of Holcomb v. Kennedy, 158 Ark. 585, where one branch of that lawsuit was reviewed and decided.
3. The appellees contend that this court, in the ■ cases of Frazier v. McHaney, 117 Ark. 394, and Meyer v. Board of Imp. Paving Dist., 148 Ark. 629, has •already decided that suits of this nature do not come within the above doctrine of class suits. The issue of res judicata was not raised in either of those cases, and, if it had been, those cases are easily differentiated on the facts from the present case, and have no application here.
In the case of Frazier v. McHaney, supra, certain railroad corporations, and a trustee for one of them, instituted an action against the Fourche Drainage District, challenging the assessments on their own lands in the district. No attack was made upon the validity of the assessment of benefits as a whole, and the action was instituted by the plaintiffs, not as a class action but simply as bn action to correct assessments against their particular property and none other. After the decree was rendered, Frazier and others-filed petitions asking to be made parties for the purpose of prosecuting an appeal to this court. We held that they were not parties to the action, and that'only those who were parties- when the decree was entered would have the right to prosecute an appeal.
In the case of Meyers v. Board of Improvement of Paving District, supra, the plaintiffs instituted the- action attacking the validity of the assessment of benefit's as-*75a whole, made under the ordinances creating improvement districts in the city of Van Burén. The statute under which the ordinances were passed, among other things, provided that “all persons who shall fail to begin legal proceedings within thirty days after, such publication for the purpose of correcting or invalidating such assessment shall be forever barred and precluded.” The action was instituted within the thirty days by the plaintiffs, Meyers and others, and some one of them, for himself and others similarly situated, who might wish to join in the action. The action therefore was a class action in which the plaintiffs represented the other taxpayers in the district similarly situated. Several months after the institution of the action, and after the time had expired in which an action could be brought for invalidating the assessment, other property owners who had not joined, by name, in the original action, asked and were permitted by the trial court to become parties plaintiff. Speaking of this ruling of the trial court, we said: “We think the court should not have permitted the new parties to be made plaintiffs. Several months had then expired since the publication of the notices of the ordinances creating the district, and the effect of the court’s action was to permit these persons, by adopting the pleadings of the persons whose names are set out above, to prosecute the° litigation which the statute required them to begin within thirty days. ’ ’ The effect of this ruling was merely to treat as new parties those who sought to come into the suit after the time when an action to invalidate the assessment of benefits could have been brought, and who then sought to be-made parties and to have the case from that time on proceed in their names to a final decree. The effect of the ruling of the trial court was to substitute these parties for those who. had originally instituted the action, and this ruling, we held,- was tantamount to the bringing of' a new suit after the time had elapsed in which a suit could have been brought.
*76The question of res judicata, as we have already said, was not raised, and the issue now under review was not considered nor ruled upon, and the language of the opinion in the case above quoted certainly would not be controlling here, and, we believe, has no application to the.facts of this record. We conclude therefore that the trial court erred in holding that there is no merit in appellant’s plea of res judicata. Having reached this conclusion, the other interesting questions so elaborately ■and ably argued in the briefs of counsel for the respective parties pass out, and it would be supererogation, pure and simple, to consider and decide them. Hence .we have not done so.
For the error indicated the .decree is reversed, and the cause is remanded with directions to dismiss the appellees’ complaint in case No. 258 for want of equity, and for such' other and further proceedings in case No. 211 as may be- necessary to enforce the collection of the •levies based on the assessment of benefits according to law, and not inconsistent with this opinion.